ofz#18554 sw: fix Null-dereference due to overlapping fieldmarks

The problem is that the WW8 import wants to set a fieldmark on a range
that contains only the CH_TXT_ATR_FIELDEND of another fieldmark:

(rr) p io_pDoc->GetNodes()[12]->m_Text.copy(33,10)
$30 = "\bÿÿÿ\001ÿÿÿ\001 "

MarkManager::makeMark() must check that a new fieldmark never overlaps
existing fieldmarks or meta-fields.

While at it, it looks like the test in
DocumentContentOperationsManager::DelFullPara() can't necessarily use
the passed rPam, because it obviously deletes entire nodes, but at
least SwRangeRedline::DelCopyOfSection() doesn't even set nContent
on rPam.

Also, the check in makeMark() triggers an assert in
CppunitTest_sw_uiwriter testTextFormFieldInsertion because
SwHistoryTextFieldmark::SetInDoc() was neglecting to subtract 1
from the end position for the CH_TXT_ATR_FIELDEND.

Change-Id: I46c1955dd8dd422a41dcbb9bc68dbe09075b4922
Reviewed-on: https://gerrit.libreoffice.org/83000
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

1 files changed, 0 insertions, 0 deletions

diff --git a/sw/qa/core/data/ww8/pass/ofz18554-1.doc b/sw/qa/core/data/ww8/pass/ofz18554-1.doc
new file mode 100644
index 000000000000..0a6b81d78b43
--- /dev/null
+++ b/sw/qa/core/data/ww8/pass/ofz18554-1.doc